Propagation analysis of plasmaspheric hiss using Polar PWI measurements
Résumé
We have analyzed high-rate waveform data, taken Storey et al. [1991] however observed hiss emissions even by the POLAR Plasma Wave Instrument at high altitudes in when, after long periods of magnetic calm, the plasmapause the equatorial plasmasphere, to study plasmaspheric hiss in the was absent. They also found that the waves often propagate at range of frequencies between 100 Hz and several kHz. These large angles from B0, even in the equatorial region. This means emissions are found almost everywhere in the plasmasphere, these waves cannot be generated exactly in the way Kennel and their origin is still controversial. Our analysis of several and Petschek [1966] suggested. These results do not directly cases shows that most of the waves were propagating more or contradict the theory of Thorne et al. [ 1973, 1979], but they do less parallel to the Earth's magnetic field, but sometimes a few suggest that under certain circumstances some other mechanism of them were propagating obliquely with their normals near may be acting. Indeed, highly oblique wave propagation fits a the Gendrin angle. Evidence of amplification was found near theory developed by Draganov et al. [ 1992], though due initially the geomagnetic equator. The results suggest that waves with to H. C. Koons; see page 19,486 of Storey et al. [1991]. On this normals both parallel and anti-parallel to the magnetic field view, hiss is simply explained by the accumulation of many were being amplified by the classical mechanism that involves whistlers trapped in the plasmasphere. gyroresonant interaction with energetic electrons. The purpose of this letter is to present the initial results from an investigation of hiss, using multi-component wave measurements by the High Frequency Waveform Receiver (HFWR) on
Domaines
Planète et Univers [physics]
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